Reply:Do some cable mods to either:
1. Feed power in via the GPIO header pins and disconnect +5 volt supply to USB-C plug.
2. Feed +5 volt into USB-C plug from PSU which can supply adequate current.
Reply
With option 1, what would be the reasoning for disconnecting power supply to USB-C? Is that because the GPIO power would conflict or that the USB-C wouldn't be able to data transfer?
To avoid a conflict between the two PSU. The higher voltage one will always try to driver the lower voltage one. Even with a tiny difference.
Personally, I use these: https://www.8086.net/products#80860016 (No, I don't get a kickback)Could I possibly use a POE+ Hat and get power through that? And if so, again, the GPiO conflict power question.
I'd expect the same problems plus I don't recall the launch of the official PoE HAT+ for the Pi5 (though I may have missed it) and the version for the 4B won't fit as the PoE pins are in a different place.
Whether you can run the Pi5 solely from the host PC depends on a number of factors:
- How much current your PC can supply (USB2 spec says don't draw more than 500mA, USB3 without PD don't draw more than 900mA). The Pi5 does do PD but only at 5v.
- If your USB host does PD it must support a 5v/5A mode or you'll run into the usual issues. Lots don't.
- What you have connected to the Pi 5, including via PCIe. Typical bare board consumption is 800mA (source https://www.raspberrypi.com/documentati ... quirements)
- How much load is on the CPU also impacts current draw. Higher load == more current.
A Y cable at the host end may help as you can draw from two ports but that'll only make a difference if your USB host actually does per port current limiting. Like Pi, not every USB host does.
Non-PD "fast charge" ports won't work if they require any sort of negotiation between source and sink (other than PD) or a specific configuration of resistors to enable them.
Unless you need the computational power of the Pi5 you might want to consider using a Pico. IIRC it can do USB device via it's built in USB H/W and USB host using a mixture of PIO and software. Much lower power requorement and no Linux impacting perforrmance. Yeah, its only at USB1 full speed but that's all you need for a mouse. IIRC not in micropython though.
Awesome suggestions, thank you.
Definitley need the computational power of the Pi 5 (4 would work as well, but would need to purchase as I have a zero)
Do we know if https://www.8086.net/products#80860016
Is compatible with the Pi 5?
Or even
https://www.8086.net/products#80860015
And with these they state you keep the OTG (Gadget Mode) functionality of the USB-C?
Statistics: Posted by MikeHope — Fri Sep 06, 2024 1:25 am